The practice of staging productions for theater and musical concerts in the same performance facility has necessitated the development of flexible stage layouts. The general purpose approach to the utilization of such facilities has encouraged the use of movable stage backdrop panels. A production team is able to set up any number of stage layouts by simply moving the needed backdrops into position on the stage floor.
Examples of stage panels supported in a generally vertical orientation range from solitary panels supporting scenery to integrated stage backdrop setups enclosing three sides of a stage with multiple panels positioned next to each other to complete the enclosure. Where more than one panel is needed, it is important that adjacent panels be correctly aligned. Each panel edge should be capable of abutting and engaging an adjacent panel edge. This is useful for presenting visually clean lines to the audience, and to ensure proper acoustics.
Additionally, the backdrop panels may have an overhead canopy with integral lighting suspended from the ceiling above the panels. The canopy panels are usually stored in a retracted position proximate the building structure over the stage area, with the canopy panel in a vertical orientation. The canopy panels capable of being raised and lowered to a performing position by means of cables running through pulleys attached to the ceiling over the stage area and rotated into a generally horizontal orientation. The panels that comprise the canopy must be capable of being angularly aligned with respect to one another in a desired relationship. The angular alignment must be repeatable to present a uniform appearance each time that the canopy panels are lowered in to the performing position.
A problem with stage lighting is the routing of power cables to the lighting. Modern stage settings require an incredible maze of power cables to power special effects and sound systems and the like. These cables are difficult to keep organized and, more seriously, present a constant danger to the stage hands. It is desirable to contain as many of the necessary cables as possible within structure in order to minimize confusion and to maximize the safety of the stage hands.
Individual stage backdrop panels may carry vertical panel components extending thirty to forty feet and may weigh as much as two thousand pounds. The vertical stage panels are carried at the front of a support base. Counter weights are carried at the back of the support base to stabilize the panel. Despite the counterweights, the center of gravity of a vertical stage panel remains well up the length of the panel, and the high center of gravity contributes significantly to the difficulty of safely maneuvering vertical stage panels. Maneuvering this much mass and achieving alignment of upwards of forty vertical feet of panelling has proven a daunting task for stage production companies that must also ensure the safety of the personnel moving the panels into place.
One example of a panel support structure useful in this area is disclosed in U.S. Pat. No. 5,115,608 issued to Abraham et al., on May 26, 1992. The '608 patent discloses a plurality of casters in clusters mounted to the base structure in at least three positions. Each caster cluster is also capable of independent height adjustment, facilitating the leveling and alignment tasks. While a useful system, problems are still encountered. The larger and heavier panel structures continue to be difficult to precisely maneuver in increments small enough to be useful to the stage crews. Considerable time is lost in repetitive alignment attempts to achieve the final fit. An additional unanticipated difficulty is encountered in those theaters where the stage floor, for whatever reason, is no longer hard, flat and smooth. Cracks and low spots can develop in stage floors which trap caster wheels. Sudden tilt, and abrupt accelerations and decelerations of the panel structures can result.
An example of a panel transport method and apparatus that combines ease of maneuverability and safety in the transport of portable, vertical stage panels of all weights and heights over uneven as well as hard, flat stage floor surfaces is disclosed in U.S. patent application Ser. 08/214,610, filed Mar. 17, 1994 and assigned to the assignee of the present invention. The transport sled disclosed therein transports the backdrop panels partially on a layer of forced air. This relieves the weight on the castors supporting the backdrop panels, permitting ease of motion over uneven stage floor surfaces and prevents the castors from damaging the stage floor surface.
It would be a decided advantage in the industry to have a moveable backdrop panel that is capable of being easily and safely repositioned and is readily alignable with adjacent backdrop panels in all axes, even on uneven stage floors without damaging the stage floors. The backdrop panels should be capable of being aligned in a variety of configurations, such as to present a curved and a straight back portion of the stage setting as desired for different performances. Once aligned, the panels should be capable of being locked in the desired positions of alignment. In addition, it would be advantageous to be able to provide electrical power to overhead lighting by means of enclosed power cables that were not exposed and therefore prone to being inadvertently disengaged. Other features that would be desirable, but have not heretofore been available include a single hinge design that is capable of selectively being configured in rotating or fixed configurations, support structure that includes a power cable channel and a hinge receiver, a canopy panel that rotates to its storage configuration by means of gravity, a releasable, and an adjustable stay for fixing the angle of the canopy panel when the canopy is in the performance configuration.